Zhuoma Wang¹, Ruoyan Li^2,3, Wenjing Ye^2,*, Yijun Liu³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.4, pp. 1-2, 2023, DOI:10.32604/icces.2023.09236

Abstract An acoustic diffuser refers to a device that spreads sound energy uniformly in all directions. Such a device plays a very important role in architectural acoustics, i.e., concert halls and auditoriums. Many designs such as the wellknown Schroeder diffusers [1] have been proposed and developed throughout the past several decades. However, most of these conventional designs achieve uniform sound diffusion by using different air trenches to create a phase shift profile following a specific sequence such as maximum length sequence or quadratic residue sequence derived from the number theory [1,2]. As such, these diffusers have… More >

Taotao Yuan¹, Haitian Yang¹, Yiqian He^1,2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.25, No.4, pp. 1-1, 2023, DOI:10.32604/icces.2023.09275

Abstract Computational modeling can provide insight into understanding the damage mechanisms of soft biological tissues, and identification of constitutive parameters is key issues in the computational modeling. On the other hand, although it is thought that computational model should be non-local for soft tissues based on the existence of intrinsic length scales, there is very few work for the identification of the parameters of nonlocal damage models of soft tissues. Firstly, we use the gradient-enhanced damage model presented in our previous publication showing advantages in considering the internal length scales and in satisfying mesh independence for More >

Israa Ismail^1,*, Mohamed Meselhy Eltoukhy^1,2, Ghada Eltaweel¹

Computer Systems Science and Engineering, Vol.45, No.1, pp. 167-181, 2023, DOI:10.32604/csse.2023.028906 - 16 August 2022

Abstract Super-resolution techniques are used to reconstruct an image with a high resolution from one or more low-resolution image(s). In this paper, we proposed a single image super-resolution algorithm. It uses the nonlocal mean filter as a prior step to produce a denoised image. The proposed algorithm is based on curvelet transform. It converts the denoised image into low and high frequencies (sub-bands). Then we applied a multi-dimensional interpolation called Lancozos interpolation over both sub-bands. In parallel, we applied sparse representation with over complete dictionary for the denoised image. The proposed algorithm then combines the dictionary More >

Christy James Jose^1,*, M. S. Rajasree²

Computer Systems Science and Engineering, Vol.44, No.2, pp. 1357-1372, 2023, DOI:10.32604/csse.2023.025672 - 15 June 2022

Abstract The predominant method for smart phone accessing is confined to methods directing the authentication by means of Point-of-Entry that heavily depend on physiological biometrics like, fingerprint or face. Implicit continuous authentication initiating to be loftier to conventional authentication mechanisms by continuously confirming users’ identities on continuing basis and mark the instant at which an illegitimate hacker grasps dominance of the session. However, divergent issues remain unaddressed. This research aims to investigate the power of Deep Reinforcement Learning technique to implicit continuous authentication for mobile devices using a method called, Gaussian Weighted Cauchy Kriging-based Continuous Czekanowski’s… More >

Mustafa Youldash¹, Saleh Al-Dossary^2,*, Lama AlDaej¹, Farah AlOtaibi¹, Asma AlDubaikil¹, Noora AlBinali¹, Maha AlGhamdi¹

Computer Systems Science and Engineering, Vol.40, No.2, pp. 619-628, 2022, DOI:10.32604/csse.2022.017733 - 09 September 2021

Abstract The seismic reflection method is one of the most important methods in geophysical exploration. There are three stages in a seismic exploration survey: acquisition, processing, and interpretation. This paper focuses on a pre-processing tool, the Non-Local Means (NLM) filter algorithm, which is a powerful technique that can significantly suppress noise in seismic data. However, the domain of the NLM algorithm is the whole dataset and 3D seismic data being very large, often exceeding one terabyte (TB), it is impossible to store all the data in Random Access Memory (RAM). Furthermore, the NLM filter would require More >

Yanfen Guo^1,2, Zhe Cui^1,*, Zhipeng Yang³, Xi Wu², Shaahin Madani⁴

CMC-Computers, Materials & Continua, Vol.61, No.3, pp. 1205-1215, 2019, DOI:10.32604/cmc.2019.06029

Abstract Since the spatial resolution of diffusion weighted magnetic resonance imaging (DWI) is subject to scanning time and other constraints, its spatial resolution is relatively limited. In view of this, a new non-local DWI image super-resolution with joint information method was proposed to improve the spatial resolution. Based on the non-local strategy, we use the joint information of adjacent scan directions to implement a new weighting scheme. The quantitative and qualitative comparison of the datasets of synthesized DWI and real DWI show that this method can significantly improve the resolution of DWI. However, the algorithm ran More >

Xianglong Su^*, Wenxiang Xu, Wen Chen

The International Conference on Computational & Experimental Engineering and Sciences, Vol.21, No.4, pp. 77-77, 2019, DOI:10.32604/icces.2019.05090

Abstract Creep of concrete can last for decades, which displays the ultra-slow rheological phenomena. As an empirical formula, the logarithmic law is usually used to describe the ultra-slow creep. However, the logarithmic law does not always work well especially for the long-term creep. And its corresponding relaxation response cannot be obtained analytically. It is known that the Mittag-Leffler and the inverse Mittag-Leffler functions are generalized from the exponential and the logarithmic functions, respectively. And the inverse Mittag-Leffler function is much slower and generalized than the logarithmic function. In this paper, we use the non-local structural derivative… More >

Liwei Wu¹, Dan Huang^1,*, Yepeng Xu¹, Lei Wang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.118, No.3, pp. 561-581, 2019, DOI:10.31614/cmes.2019.04347

Abstract Strain hardening and strain rate play an important role in dynamic deformation and failure problems such as high-velocity impact cases. In this paper, a non-ordinary state-based peridynamic model for failure and damage of concrete materials subjected to impacting condition is proposed, taking the advantages of both damage model and non-local peridynamic method. The Holmquist-Johnson-Cook (HJC) model describing the mechanical character and damage of concrete materials under large strain, high strain rate and high hydrostatic pressure was reformulated in the framework of non-ordinary state-based peridynamic theory, and the corresponding numerical approach was developed. The proposed model More >

A.I. Dimitriadis¹, N.V. Kantartzis¹ and T.D. Tsiboukis¹

CMC-Computers, Materials & Continua, Vol.39, No.3, pp. 231-265, 2014, DOI:10.3970/cmc.2014.039.231

Abstract The most important surface susceptibility models for the electromagnetic characterization of periodic metafilms, based on the dipole approximation method, are systematically analyzed in this paper. Specifically, two well-known techniques, which lead to a set of local effective surface parameters, are investigated along with a new dynamic non-local modeling algorithm. The latter formulation is properly expanded, in order to be applicable for any arbitrary periodic metafilm, irrespective of its way of excitation. The featured schemes are then directly compared toward their ability to efficiently predict the reflection and transmission properties of several lossless and lossy metafilms. More >

V. Mallardo, C. Alessandri¹

Structural Durability & Health Monitoring, Vol.2, No.3, pp. 165-176, 2006, DOI:10.3970/sdhm.2006.002.165

Abstract The formation of cracks and their propagation in brittle materials has been intensively studied in the last years. The main difficulty is related to the theoretical and numerical possibility to follow the development of regions of highly localised strains. The nonlinear phenomenon is physically different from the one which occurs in ductile materials: it starts with a narrow fracture process zone containing a large number of distributed microcracks which could lead to the formation of macrocracks and eventually to rupture. In the present paper, a simple nonlocal damage model is coupled to the crack analysis More >